JPS61210969A - Method for plotting accident point of cable line - Google Patents

Abstract

PURPOSE:To plot an accident point position at high accuracy by using an optical fiber cable when a discharging pulse orienting to a remote terminal from an accident point is transmitted to a measuring terminal. CONSTITUTION:A calibrating pulse is impressed on the remote terminal of an accidental cable line 2, and a synchroscope SS 9 measures a time difference deltat between a pulse detected at a measuring point through the line 2 and a pulse which is transmitted through an electrical/optical converter 4, the optical fiber cable 5 and an optical/electrical converter 6 and detected at the measuring terminal 3. Then assuming that a high voltage is impressed on the line 2 from the measuring terminal 3 and the discharging pulse occurs at the accident point A, the pulse is detected as the 1st propagation signal S1 at the measuring termi nal 3 of the line 2 by means of the SS 9. The discharging pulse is also detected as the 2nd propagation signal S2 at the remote terminal of the line 2, and trans mitted to the converter 6 through the converter 4 and the cable 5, thereby calculating a time difference DELTAt between the signals S1 and S2 by means of the SS 9. And a distance S from the measuring terminal 3 to the point A is obtained with the prescribed equation where the length of the line 2 and a pulse propagation speed through the line 2 are L and V, respectively.

Description

【発明の詳細な説明】 ［発明の技術分野］ 本発明は、ケーブル線路の事故点標定法に係り、特に、
事故点が高精度で迅速に標定できるケーブル線路の事故
点標定法に間する。[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a method for locating fault points on cable lines, and in particular,
A method for locating accident points on cable lines that allows accident points to be located quickly and with high accuracy is developed.

［発明の技術的背景］ 従来から、ケーブル線路の事故点標定法として第２図に
示すように、事故相のケーブル線路の事故点Ａで発生し
た放電パルスを該ケーブル線路の測定端においてコンデ
ンサＣとインピーダンスＺにより第１の伝播信号Ｓｔと
して検出すると共に、該放電パルスを該ケーブル線路の
遠方端において接続された健全相のケーブル線路を介し
て伝送し、測定端においてコンデンサＣとインピーダン
スＺにより第２の伝播信号Ｓ２として検出し、増幅器ｌ
Ｏを介しシンクロスコープ１２上でオシログラムで標定
する方法が知られている。このときのオシログラムの代
表例を第３図に示すと、第１の伝播信号Ｓｌは事故点Ａ
から測定端に直接伝播したパルス、第２の伝播信号Ｓ２
は事故点Ａから遠方端において接続された健全相を伝送
して測定端に伝播したパルスを示している。従って、測
定端における第１の伝播信号−Ｓｌおよび第２の伝播信
号Ｓ２の時間差Δｔはパルスが事故点Ａと遠方端を往復
伝播した時間であり、測定端から事故点Ａまでの距ａＸ
はパルスの伝播速度Ｖから次式で求められる。[Technical Background of the Invention] Conventionally, as shown in Fig. 2, as a fault point locating method for cable lines, a discharge pulse generated at a fault point A of a cable line in a fault phase is connected to a capacitor C at the measuring end of the cable line. The discharge pulse is detected as the first propagation signal St by the impedance Z, and the discharge pulse is transmitted through the cable line of a healthy phase connected at the far end of the cable line, and the first propagation signal St is detected by the capacitor C and the impedance Z at the measurement end. 2 as the propagation signal S2, and the amplifier l
A method of locating with an oscillogram on the synchroscope 12 via O is known. A typical example of the oscillogram at this time is shown in FIG. 3. The first propagation signal Sl is at the fault point A.
The pulse directly propagated from to the measurement end, the second propagation signal S2
indicates a pulse transmitted from the fault point A through the healthy phase connected at the far end and propagated to the measurement end. Therefore, the time difference Δt between the first propagation signal -Sl and the second propagation signal S2 at the measurement end is the time during which the pulse propagated back and forth between the fault point A and the far end, and the distance aX from the measurement end to the fault point A
is determined from the pulse propagation velocity V by the following equation.

Ｘ＝Ｌ−Ｖ△ｔ／２ ここでＬはケーブル長である。X=LV△t/2 Here, L is the cable length.

［背景技術の問題点コ このような事故点標定法は、線路がクロスボンド方式で
接地されている場合、絶縁接続箱で事故相から健全相へ
放電パルスの伝播波が分波される誘導が生じ、遠方端か
ら帰って来る伝播波と区別できなくなるため、時間差Δ
ｔが不明確となり、事故点の位置標定かできなくなると
いう難点がある。[Problems with the background art] This method of locating the fault point is such that when the line is grounded using a cross-bond method, the propagating wave of the discharge pulse is split by the insulating junction box from the fault phase to the healthy phase. The time difference Δ
There is a problem that t becomes unclear and the position of the accident point cannot be determined.

またこの場合、線路の絶縁接続箱を普通接続箱に変更し
た後、上記測定を行なっており、絶縁接続箱の変更工事
に多大な労力と時閉を費やしている。この種事故点は一
刻も早く発見する必要があるにも拘らず、上記変更工事
は最大の難点となっている。Further, in this case, the above measurements are performed after the insulated junction box of the line is changed to a normal junction box, and a great deal of labor and time is expended in the work to change the insulated junction box. Although it is necessary to detect this kind of accident point as soon as possible, the above modification work has become the biggest difficulty.

［発明の目的］ 本発明は上記従来の難点に鑑みなされたもので、事故点
が高精度で迅速に標定できるケーブル線路の事故点標定
法を提供せんとするものである。[Object of the Invention] The present invention has been made in view of the above-mentioned conventional difficulties, and it is an object of the present invention to provide a method for locating fault points on cable lines, which allows fault points to be located quickly and with high accuracy.

［発明の概要］ このような目的を達成するために本発明のケーブル線路
の事故点標定法によれば、ケーブル線路の事故点で発生
した放電パルスを該ケーブル線路の測定端において第１
の伝播信号として検出すると共に、該放電パルスを該ケ
ーブル線路の遠方端において第２の伝播信号として検出
して電気／光変換器から光ファイバケーブルにより測定
端に設けた光／電気変換器に伝送し、測定端において第
１の伝播信号および第２の伝播信号の時間差を算出して
ケーブル線路の事故点を標定するものである。[Summary of the Invention] In order to achieve such an object, according to the cable line fault point locating method of the present invention, a discharge pulse generated at a cable line fault point is first detected at the measurement end of the cable line.
At the same time, the discharge pulse is detected as a second propagation signal at the far end of the cable line, and transmitted from the electric/optical converter to the optical/electrical converter provided at the measuring end by an optical fiber cable. The fault point on the cable line is located by calculating the time difference between the first propagation signal and the second propagation signal at the measuring end.

［発明の実施例］ 以下、本発明の好ましい実施例を図面により説明する。[Embodiments of the invention] Preferred embodiments of the present invention will be described below with reference to the drawings.

本発明のケーブル線路の事故点標定法は第１図に示すシ
ステム構成により実現される。即ち、同図において、ケ
ーブル線路２の測定端は高電圧を印加する端子３に接続
されていると共に、コンデンサＣ５インピーダンスＺを
介して接地される。The cable line accident point locating method of the present invention is realized by the system configuration shown in FIG. That is, in the figure, the measuring end of the cable line 2 is connected to the terminal 3 for applying a high voltage, and is also grounded via the impedance Z of the capacitor C5.

コンデンサＣとインピーダンスＺの中間点は増幅器８に
接続されている。一方、ケーブル線路２の遠方端はコン
デンサＣ、インピーダンスＺを介して接地され、コンデ
ンサＣとインピーダンスＺの中間点は電気／光変換器４
に接続されている。測定端には光／電気変換器６が設け
られ、電気／光変換器４と光／電気変換器６は光ファイ
バケーブル５により接続されている。光／電気変換器６
の出力端は増幅器８に接続されている。増幅器８の出力
端はシンクロスコープ９に接続されている。The midpoint between capacitor C and impedance Z is connected to amplifier 8. On the other hand, the far end of the cable line 2 is grounded via a capacitor C and an impedance Z, and the midpoint between the capacitor C and the impedance Z is connected to an electrical/optical converter 4.
It is connected to the. An optical/electrical converter 6 is provided at the measurement end, and the electric/optical converter 4 and the optical/electrical converter 6 are connected by an optical fiber cable 5. Optical/electrical converter 6
The output terminal of is connected to an amplifier 8. The output end of the amplifier 8 is connected to a synchroscope 9.

このようなシステム構成において本発明によるケーブル
線路の事故点標定は次のような手順により行なわれる。In such a system configuration, fault point location on a cable line according to the present invention is performed by the following procedure.

■　事故ケーブル線路２の遠方端に校正用パルスを印加
し、この事故ケーブル線路を伝播して測定端で検出され
るパルスと電気／光変換器４、光ファイバケーブル５、
光／電気変換器６により伝送されて測定端において検出
されるパルスとの時間差δｔをシンクロスコープ９上の
オシログラムで測定する。この時間差δｔは事故ケーブ
ル線路２による伝送系みに対する電気／光変換器４、光
ファイバケーブル５、光／電気変換器６による伝送系に
おけるパルス信号の時間遅れを予め校正するためのもの
である。■ A calibration pulse is applied to the far end of the faulty cable line 2, and the pulse is propagated through the faulty cable line and detected at the measurement end, and the electric/optical converter 4, optical fiber cable 5,
The time difference δt between the pulse transmitted by the optical/electrical converter 6 and detected at the measuring end is measured with an oscillogram on the synchroscope 9. This time difference δt is used to calibrate in advance the time delay of the pulse signal in the transmission system including the electrical/optical converter 4, the optical fiber cable 5, and the optical/electrical converter 6 with respect to the transmission system based on the faulty cable line 2 only.

■　事故ケーブル線路２に端子３から高電圧を印加する
。放電パルスが例えば事故点Ａで発生したものとする。■ Apply high voltage to the faulty cable line 2 from terminal 3. Assume that a discharge pulse occurs at a fault point A, for example.

この放電パルスをケーブル線路の測定端においてシンク
ロスコープ９上のオシログラムで第１の伝播信号Ｓ１と
して検出する。また、この放電パルスをケーブル線路の
遠方端において第２の伝播信号Ｓ２として検出して電気
／光変換器４、光ファイバケーブル５により測定端に設
けた光／を気変換器６に伝送し、測定端においてシンク
ロスコープ９上のオシログラムで第１の伝播信号Ｓ１お
よび第２の伝播信号Ｓ２の時間差Δｔを算出する。This discharge pulse is detected as a first propagation signal S1 by an oscillogram on a synchroscope 9 at the measurement end of the cable line. In addition, this discharge pulse is detected as a second propagation signal S2 at the far end of the cable line, and the light / provided at the measurement end is transmitted to the air converter 6 by the electric/optical converter 4 and the optical fiber cable 5. At the measurement end, a time difference Δt between the first propagation signal S1 and the second propagation signal S2 is calculated using an oscillogram on the synchroscope 9.

■　測定端から事故点Ａまでの距ａＸはケーブル線路長
２をし、ケーブル線路２中のパルスの伝播速度をＶとす
れば、 Ｘ＝Ｌ−Ｖ　　（Δ　ｔ−＆ｔ）／２ としてケーブル線路の事故点が標定される。■ The distance aX from the measurement end to the fault point A is the cable line length 2, and the pulse propagation speed in the cable line 2 is V, then the cable line is The accident point is located.

なお、伝播速度Ｖは測定端にパルスを印加し、■と同種
の時間差ΔＴを測定すれば、 Ｖ＝＝２Ｌ／　（ΔＴ−Δｔ） として求められる。Note that the propagation velocity V can be obtained as V==2L/(ΔT−Δt) by applying a pulse to the measurement end and measuring the same type of time difference ΔT as in (2).

〔発明の効果コ 以上の実施例からも明らかなように本発明のケーブル線
路の事故点標定法によれば、クロスボンド方式で接地さ
れている場合でも事故点から遠方端へ向かう放電パルス
を測定端へ伝送する際に光ファイバケーブルを使用する
ようにしたので、クロスボンドによる誘導の影響を受け
ない高精度の事故点位置標定かできる。[Effects of the Invention] As is clear from the above embodiments, according to the fault point locating method for cable lines of the present invention, discharge pulses directed from the fault point to the far end can be measured even when the cable line is grounded by the cross-bond method. Since an optical fiber cable is used for transmission to the end, it is possible to locate the accident point with high precision without being affected by guidance by cross bonds.

また、ケーブル線路の絶縁接続箱を普通接続箱に変更す
る工事が不要なため、大幅な時間短縮が可能で迅速に事
故点標定ができる。Additionally, since there is no need to change the insulated junction box of the cable line to a normal junction box, it is possible to significantly reduce time and quickly locate the accident point.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図は本発明によるケーブル線路の事故点標定法を実
現するためのシステム構成図、第２図は従来の事故点標
定法に用いられるシステム構成図、第３図は同標定法で
得られる放電パルス伝播１Ｂ号の波形図である。 ２８０．ケーブル線路 Ａ１０．事故点 Ｓｌ、、、第１の伝播信号 Ｓ２．、、第２の伝播信号 ４００．電気／光変換器 ６１０．光／電気変換器 ５１０．光ファイバケーブル Δｔ１９１時間差Figure 1 is a system configuration diagram for realizing the cable line accident point locating method according to the present invention, Figure 2 is a system configuration diagram used in the conventional accident point locating method, and Figure 3 is the system configuration obtained by the same locating method. It is a waveform diagram of discharge pulse propagation No. 1B. 280. Cable line A10. Fault point Sl, , first propagation signal S2. ,, second propagation signal 400 . Electrical/optical converter 610. Optical/electrical converter 510. Optical fiber cable Δt191 time difference

Claims (1)

【特許請求の範囲】[Claims] ケーブル線路の事故点で発生した放電パルスを該ケーブ
ル線路の測定端において第１の伝播信号として検出する
と共に、該放電パルスを該ケーブル線路の遠方端におい
て第２の伝播信号として検出して電気／光変換器から光
ファイバケーブルにより測定端に設けた光／電気変換器
に伝送し、測定端において第１の伝播信号および第２の
伝播信号の時間差を算出してケーブル線路の事故点を標
定することを特徴とするケーブル線路の事故点標定法。The discharge pulse generated at the fault point of the cable line is detected as a first propagation signal at the measuring end of the cable line, and the discharge pulse is detected as a second propagation signal at the far end of the cable line to generate an electric/ The signal is transmitted from the optical converter via an optical fiber cable to the optical/electrical converter installed at the measurement end, and the time difference between the first propagation signal and the second propagation signal is calculated at the measurement end to locate the fault point on the cable line. A method for locating accident points on cable lines, which is characterized by the following.